The actual cause of a ganglion cyst is not known. However, it seems that women are more susceptible than men. Also, ganglions are commonly found in gymnasts, who repetitively put pressure on their wrists. Some cases of ganglion cysts can be more painful since the fluid-filled sac gives pressure on those nerves that pass via the joint. Bigger ganglions are unattractive even if they aren’t causing any pain. On the other hand, smaller ones that stay hidden under your skin called occult ganglions can be more painful. In some cases, an MRI or ultrasound will be required to identify a ganglion cyst that is hidden underneath your skin.